I would like to use my own custom logo on the header rather than a header image. I have edited other themes to add my own logo but I cannot figure it out with this theme. Any help is appreciated, thanks!

Maybe this needs its own post, but the logo I created does not fit well on the screen when using a mobile device, such as an iPhone. The text also seems too narrow, how do I go about widening the appearance of the site on a mobile device? It looks fine on a computer.

I've tried everything short of modify the template to replace my home page header graphical image. I returns even after I delete it. I'm currentyly suing the default image provided. I'm not sure using a child theme will work.
There shoudl be a smily way to delete and replace this image. Can anyone help.